Mosquito-borne arboviral diseases such as dengue and chikungunya have continuously been a major global public health concern. Introducing the intracellular bacterial endosymbiont Wolbachia into mosquito populations has been proven to reduce dengue virus transmission, and its broader efficacy against other arboviruses has also been investigated. Several Wolbachia strains have been successfully propagated in insect cell lines, highlighting the utility of in vitro systems for studying microbial-host interactions under controlled conditions. This study investigated the initial establishment and replication kinetics of a flea-derived Wolbachia strain (wCfe), which was originally isolated from Malaysian Ctenocephalides felis and maintained in the Ixodes scapularis tick-derived cell line (IDE8), and then transferred into an Aedes albopictus-derived cell line (C6/36). The wCfe strain was semi-purified from IDE8 cultures and inoculated into C6/36 cells in 24-well plates. Replication dynamics were monitored by quantitative real-time PCR targeting the Wolbachia pipientis 16S rRNA gene. Following infection, a lag phase was observed at day 0 to 5 days post-infection (d.p.i.), followed by exponential growth from 6 d.p.i. after which Wolbachia levels remained relatively stable until the end of the observation period at 12 d.p.i. Overall, a 25.30-fold increase in Wolbachia density was detected relative to 0 d.p.i. Across replicates, the estimated generation time of wCfe in C6/36 cells ranged from 1.7 to 2.5 days. These results demonstrate successful initial establishment and replication of the flea-derived Wolbachia strain in the Aedes mosquito cell line. However, longer-term in vivo studies will be necessary to determine the persistence of wCfe infection in C6/36 cells and within the mosquito host.

Low levels of serum 25(OH)D in women are reported in temperate countries, and increasingly so in tropical countries but few such studies have been reported in Indonesia. This study was aimed at assessing the serum vitamin D status and its associated factors in a sample of Indonesian women Methods: A cross-sectional study was conducted on 156 apparently healthy women during the dry season in North Sumatera. The measurements carried out included exposure to sun's rays, intake of vitamin D food sources, reported physical activity, body fatness (by bioelectrical impedance analysis), and serum 25(OH)D levels (by chemiluminescent immunoassay). Serum 25(OH)D levels were categorised into: deficient(<20 ng/mL), insufficient (20-32 ng/mL), sufficient (32-100 ng/ mL), and normal for tropical countries (54-90 ng/mL). Statistical analysis included Pearson correlation, independent t-test, and one way ANOVA tests. Results: The mean age of the subjects was 35.6±7.7 years, with about 70% working indoors. About half of the women were obese. The majority had low vitamin D intake. More than half had sun ray exposure of less than 1 hour, and moreover, nearly two-thirds of them wore the 'hijab' that covers most parts of their body. The majority of women reported low physical activity level. The mean serum 25(OH)D level of the subjects was 17.71 ng/mL (95% CI: 16.22, 19.34 ng/mL). Of the total, 95% (148) were in the vitamin D deficient-insufficient category, with the remaining 5% in the sufficient category. An association was found between occupation, dietary intake of vitamin D, sun ray exposure, and physical activity levels with serum vitamin D concentrations. Conclusion: The results showed that vitamin D deficiency can occur in women living in a tropical country if they have sun-avoiding lifestyles, work indoors, and have low dietary intake of vitamin D.
Vitamin D ; Women ; Indonesia